Brainstorming "verified" IndieWeb checkins

Checkins can easily be faked. The Foursquare app does a reasonable job of preventing fake (and accidental fake) checkins, but it's still possible. If checkins weren't posted on Foursquare, but instead were posted on each person's own website, the possibility of fake checkins is much greater. What would it look like to have a way for a venue to know (and republish) checkins that it knows were real?

The checkin post would need to include some piece of information that could only have been discovered by physically being at the venue.

What if:

The venue has a website that receives Webmentions and supports verified checkins.

you’d need to tolerate some reuse of codes, due to the overlap of multiple people seeing the same code and taking a bit of time to post it, so it’d maybe be more like “probably verified.” you could definitely find ways to extend it to handle that, but they might complicate the UX too much.

There's a race condition for people checking in at once. It would make more sense to tie the unique tokens to something that the venue wants to ration or track, like tables, order numbers or wifi tokens.